Neurologie, neurochirurgie dereglări vasculare medulare ischemice în leptopahimeningită fibrozantă D. Gherman, E. Gavriliuc Catedra de Neurologie, usmf „N. Testemiţanu”

Rezumat

Simptomele clinice şi neurofiziologice ale meningiomului spinal

Studiul clinic şi electrifiziologic s-a bazat pe investigaţie a 27 de pacienţi cu meningiom spinal. Toate cazurile au fost confirmate prin RMN şi examenul histologic. Examenul electrofiziologic a constatat din EMG cu ac-electrod al muşchilor: paravertebralis, vastus lateralis, biceps femoris, tibialis anterior and gastrocnemius medialis. Rezultatele examenului electrofiziologic şi clinic în fiecare caz au fost correlate cu nivelul de leziune spinală.

Dereglările electrofiziologice au fost detectate în 100% de cazuri. Basându-se pe analiza statistică, criteriile electrofiziologice au fost elaborate pentru a determina fiecare sindrom al meningiomului spinal. Adăugător acestor rezultate au fost stabilite: dereglări compresive ale cordului spinal, reorganizarea morfofuncţională a unităţilor motorii şi aparatului segmentar neuro-muscular. Ca rezultatul plasticităţii neuronale la acest nivel al sistemului nervos au fost stabilite programe noi de conductabilitate motorie.

Concluzia generală acestui studiu este că examinarea electrofiziologică multimodală în contuitatea examenului clinic neurologic este foarte importantă în diagnosticul pozitiv şi diferenţial al meningiomului spinal. Studiul electrofiziologic este foarte util şi în prognozarea procesului tumoral spinal şi pentru controlul eficacităţii tratamentului neurochirurgical.

Introduction

The annual incidence of primary spinal neoplasms ranges from 0.8 to 2.5 per 100,000 population(Fogelholm et al 1984). In hospital neurosurgical practice, intraspinal neoplasms generally account for approximately 15% of all primary tumors of the central nervous system. A large series of 1322 primary intraspinal tumors, reported from the Mayo Clinic, recorded an incidence of 29% schwannomas, 25.5% meningiomas, 22% gliomas, and almost 12% sarcomas (Slooff et al 1964). Meningiomas in the spinal canal are far less frequent than those within the cranial cavity (Elsberg 1925;Slooff et al 1964;Russell and Rubinstein 1989).

The majority of spinal meningiomas present in the older population, with a peak in the sixth decade. Meningiomas are rare in children and young adults. In this age group there is an increase of malignant variants when compared to adults and a higher association with neurofibromatosis (Deen et al 1982;Nakamura and Becker 1985). Familial occurrence of meningiomas, usually multiple, is found largely in the context of von Recklinghausen disease(Delleman et al 1978).

Spinal meningiomas have a female preponderance of up to 90% (Nittner 1976;Solerno et al 1989;Roux et al 1996;King et al 1998).

The high diagnostic-prognostic value reached by the clinical neurophysiology investigations has contributed to bring the clinical neurophysiologist in the forefront. Patterns of referral for clinical neurophysiology investigation have changed greatly over the past ten years, the most interesting datum being a steady rise in the number of electromyography (EMG) requests. At the present time, most clinical neurophysiology studies in spinal meningioma are faced with operational deficits, evidencing significant discrepancies between EMG reimbursable costs and operating costs. The corrective strategies empirically adopted until now, have paradoxically produced effects opposite to those expected.

AIMS

There appears to be need to carry out a systematic, in-depth analysis of the clinical – imagistic – EMG analysis of spinal meningiomas, which will require the commitment collaboration of neurologist, neurosurgeon, neuroimagist and neurophysiologist.

The continuous increase in the demand for neurophysiological diagnostic testing and the consequent diagnostic flourishing of a not always qualitatively homogeneous supply in spinal meningioma, indicate the need for the following actions:

• 
  to proceed to the development of clinical practice guidelines for the diagnosis of the spine cord compression, establishing the minimum qualitative criteria required;
  
• 
  to construct a reference table with the time required to perform EMG diagnostic tests, keeping in mind the standards of quality.
  

Materials and methods

Twenty seven patients who met the diagnostic criteria for spinal meningioma were included in the study. All of the patients were evaluated in our hospital over a period of 5 years (2001-2006) according to a predefined protocol. At the time of diagnosis, all patients underwent: clinical evaluation, MRI examination and electrophysiologic examinations. In all 27 patients diagnosis was confirmed by morphological examination.

Clinical evaluation

Patient disability was assessed at baseline, after six and 12 months, and at the end of follow-up, according to a modified Rankin scale scores were: 0 = asymptomatic; 1 = nondisabling symptoms that do not interfere with lifestyle; 2 = minor symptoms that lead to some restriction in lifestyle, but do not interfere with patients’ capacity to look after themselves; 3 = moderate symptoms or prevent totally independent existence; 4 = moderately severe symptoms that clearly prevent independent existence, although patient does not need constant attention; 5 = severely disabled, totally dependent, requiring attention.

Electrophysiologic examination

All patients had needle electromyographic examination of the paravertebralis,vastus lateralis, biceps femoris, tibialis anterior and gastrocnemius medialismuscles. Conduction studies were performed using standard techniques. Motor conduction of median, ulnar, peroneal and tibial nerves was assessed. For motor nerves, F response latencies, compound muscle action potential (CMAP) amplitudes and duration, conduction velocities, distal latencies, and the proximal/distal CMAP amplitude ratios were evaluated. Sensory nerve action potentials (SNAPs), and amplitude and conduction velocities (onset latencies) were recorded from the median or ulnar nerves and from the sural nerves. All twenty seven patients had repeat electrophysiologic examinations.

Results

Clinical features and disease and disease course are summarized in Table 1. Clinical disability was mild (Rankin ≤ 2) in 67% of patients, moderate (Rankin = 4) in 8%.

Fourteen patients had both motor and sensory involvement, twenty one had predominant motor deficit, while nine had mainly sensory symptoms. Lower limbs were predominantly involved in 15 cases, all limbs were resulted similarly affected in 22 cases, and upper limbs were mainly affected in 3 patients.

Table 1 Characteristics of the 27 spinal meningioma patients

Clinic syndrome	Level			Total
	cervical	thoracic	thoracic –lumbar
Radicular	-	2	-	2
Hemisection of the cord (Brown / Séquard)	6	11	-	17
Complete transverse lesion	-	7	1	8

Electrophysiological evaluations of the patients with spinal meningiomas showed persistent and disperse spontaneous muscular activity like fibrillation potentials, fasciculations and sharp waves in the all examined muscles unrelated with medullar lesions (fig.1).

Fibrillation potentials and sharp waves in the next muscles: paravertebralis,vastus lateralis, biceps femoris, tibialis anterior and gastrocnemius medialis, didn’t correlate with neurological manifestations, being registered in the paraparesis and paraplegia phases as well. Any relations between expression of spontaneous muscular activity, spasticity degree and severity of medullar lesion determined by MRI-exam were established.

In 12 patients EMG abnormalities had been solved in 8-11 weeks parallel with restoration of voluntary control of the affected muscles after performed surgical treatment. Statistical analysis revealed approach of the medium values of the fibrillation potentials amplitudes and sharp waves in the patients with ischemic medullar strokes, these values constituted 112 and 126 mV.

Fig. 1. EMG examination showing a denervation activity: positive sharp waves.
Motor units potentials (MUP) with abnormal duration values and amplitudes were noticed at least in too muscles of all the patients with spinal meningiomas. Finding of this deviation from normal values was performed by comparison of obtain results with MUP values in the group control. Comparative analysis of the basic components of the motor units in the patients with chronic vascular myelopathy showed direct connection between duration values and amplitudes, basic potentials amplitudes and summary amplitude of MPU (r=0,95, P<0,001). These results were compared with the evolution stage of the pathological process. Obtained results showed that next studies of the denervation-reinervation process configuration of the basic component remain the same, but variability of the duration and total surface of the MPU is determined by the unstable components and satelit-potentials. MPU with unstable components at the end of potential predominate in the early phase of the reinervation, which is the first week after neurosurgical treatment. By the time as reinervation process is extended in the interior of the muscle, unstable components are changed by satelit-potentials; in the advanced stages of the reinervation-denervation process, clinically expressed by subcompensated-decompensated phase, basic component of the MPU is constant associated with Jitter phenomenon (fig. 2). The scientific group of Wakeling recently discussed this phenomenon.


Fig. 2.Jitter phenomena registered from the left tibial anterior muscle at the patient with spinal meningioma of Th6-Th9 spinal cord level after surgical remove.
In the miotom innervated by chronically compressed medullar segments by the neoplasic process number of the motor unit’s polyphasic potentials was elevated constantly. Signs of the peripheral motoneuron lesions in the case of the polyphasic PUM are:

• 
  from the total number of the registered potentilas polyphasic ones are more that 16%
  
• 
  internal and external aspects of the polyphasic potential is modified as well;
  
• 
  amplitude and duration of the polyphasic potential increase in correlation with denervation-reinervation process.
  

Statistical analysis didn’t establish concludent corellation between phases number of polyphasic MUP and denervation-reinervation process phase (p>0,05), as well as percentage of the polyphasic MUP and evolutive stage of the spinal meningiomas (p<0,1).

Second exam of the MUP in 16 patients with motor disturbances in the muscles of the upper and lower extremities permitted to establish three classes of survived motor units: 1) MUP which are controlled voluntary with the same level of the excitability as in the control group; 2) MUP with spontaneous involuntary activation, number of which is varying upon the expression of the paresis or paralysis; 3) MUP which can be activated slow and weak.

Between class of survived MUP in the spinal meningiomas patients were observed 3 subgroups additionally: a) MUP of the regular form (2-4 phases); b) polyphasic MUP (5 or more phases); false polyphasic MUP-special type of MUP with regular number of phases, but with additional oscillations in the positive and/or negative portions that don’t come to isoelectric level. (fig. 3)



Fig. 3.Polyphasic potentials with „turnover” of MUPs after one week post-surgical remove of spinal meningioma registered from the vastus lateralis dexter muscle at the patient with spinal meningioma of thoracic level.
In all the patients with severe paresis predominate the class of the motor units that can be slowly and weakly activated (from 43 to 76% from all survived MUP). This kind of patient have being told to stop voluntary activity realized the request in 5-10 sec. In case of the activation these potentials can be registered and analyzed constantly.

Conclusions

1. 
   Complex utilization of the clinical, imagistical examination (CT-myelography, MRI, selective spinal angiography) and needle-EMG enhances knowledge of the muscular denervation process pathogeny by chronic progressive medullar compression, allows functional evaluation of the spinal cord and patients monitoring in the early and late pos-surgery stage.
   
2. 
   Persistent spontaneous muscular activity like fibrillations and sharp waves registered by needle-EMG is typical electrophysiological phenomenon in spinal meningiomas patients with different localization
   
3. 
   Slowly progressive spinal meningioma leads to morpho-functional reorganization of the motor units and segmentar neuro-motor apparatus with installation of the specific potentials for different phase of the medullar compression evolution. Needle-EMG exam of the muscles innervated by medullar segments adjacent to ischemic process revealed existence of three classes between survived motor units potentials (MUP).
   

References cited

1. Calogero J.A., Mossy J., Extradural spinal meningiomas. Report of four cases. J Neurosurg, 1972, 37: 442-447.

2. Harkey H.L., Crockard H.A., Spinal meningiomas: Clinical features. In Al-Mefty O. (ed): Meningiomas Raven Press, New York, 1991: 593-601.

3. Jenny B., Rilliet B., May D., et al.,Abord transthoracique transvertebral pour resection d’un méningiom calcifié de situation antérieure. Neurochirurgie 2002, 48: 49-52.

4. Klekamp, Samii, Spinal meningiomas. Surg. Neurol, 1999, 52: 552-562.

5. Nittner K., Spinal meningiomas, neurinomas and neurofibromas and houglass tumors. In: Vinken P.J., Broyn G.W .(eds). Handbook of clinical Neurology, vol. 20. Amsterdam. North-Holland Publishing, 1976: 179-322.

6. Raez M.B., Hussain M.S., Mohd-Yasin F., Techniques of EMG signal analysis: detection, processing, classification and applications. Biol Proced Online, 2006, 8:11-35.

7. Russel D., Rubinstein L.J.,Pathology of Tumours of the Nervous System.London: Edward Arnold LTD, 1959.

8. Solero C.L., Fornari M., Giombini S., et al., Spinal meningiomas: review of 174 operated cases. Neurosurgery 1989, 25: 153-160.

9. Stern J., Whelan M.A, Correll J.W.,Spinal Extradural meningiomas. Surg. Neurol, 1980, 14: 155-159.

10. Wakeling J.M., Uehil K., Rozitis A.I., Muscle fibre recruitment can respond to the mechanics of the muscle contraction. J. R. Interface, 2006, 3(9): 533-544.


ASPECTUL CORELATIV AL MANIFESTĂRILOR CLINICE ŞI ELECTROENCEFALOGRAFICE ÎN EPILEPSIA CATAMENIALĂ

Victoria Duca

Centru Naţional Ştiinţifico-Practic Medicină de Urgenţă, Departamentul de Neurologie

Summary

Correlative aspect of clinical and electroencephalographic

manifestation in the caramenial epilepsy

The clinical observation of the relationship between epileptic seizure and the menstruation of women, lead to a common belief that seizures, sometimes, occur more frequently in relationship to menstrual cycle. Catamenial epilepsy is considered as a menstrual cycle-related seizure disorder and is characterized by an increase in seizures during particular phases of the menstrual cycle. The relationship between seizures exacerbation and cerebral discharges is less elucidate and is controversial.

Rezumat

Corelaţia dintre crizele epileptice şi perioada ciclului menstrual la femei a dedus idea unui caracter mai ritmic al crizelor în dependenţă de faza menstruaţiei.. Epilepsia catamenială este definită ca o disfuncţie dependentă de faza ciclului menstrual şi se caracterizată printr-o majorare a ritmicităţii crizelor pe parcursul anumitor perioade a menstruaţiei. Corelaţia dintre exacerbările crizelor şi descărcărilor cerebrale este controversat şi neelocvent.

Actualitatea

Epilepsia catamenială este definită ca „o majorare marcantă a frecvenţei crizelor epileptice către menzis”.(1) Se consideră că, aceste crize sunt induse de hormonii steroizi reproductivi , estrogenul şi progesteronul, care posedă proprietăţi neuroactive.(4) Proprietăţile neuroactive şi variaţia ciclică a concentraţiei lor plasmatice sunt factori patofiziologici importanţi în declanşarea procesului epileptogen. Studii recente au demonstrat şi confirmat existenţa a 3 pattern–uri în exacerbarea crizelor catameniale: premenstrual şi ovulator în ciclul menstrual ovulator şi faza luteală în întregime în ciclul anovulator. Incidenţa crizelor catameniale este de aproximativ 30% după A.Herzog, care consideră drept criteriu de apreciere a crizelor catameniale majorarea lor dublă în diferite pattern–uri. După alţi autori incidenţa variază de la 12 la 78%, în dependenţă de criteriu aplicat.(10)

Frecvenţa crizelor focale în epilepsia catamenială este joasă în faza luteală a ciclului ovulator, în timp ce se majorează în menzis şi ovulaţie (5). În ciclul menstrual anovulator frecvenţa crizelor se poate majora începând cu a 10 zi şi ocupă toată faza luteală. Diminuarea crizelor în ambele pattern-uri se datorează efectelor anticonvulsivante ale progesteronului. Crizele tonico-clonice primar sau secundar generalizate sunt mai ciclice decât alte tipuri (6). Durata crizelor catameniale în diferite pattern-uri nu pare a fi alternantă (2). Perioada postictală prezintă în majoritatea sa cefalee şi somnolenţă.(8).

Ca valoare de diagnostic se consideră aceleaşi criterii, în baza cărora se confirmă diagnosticul de criză epileptică – stereotipismul semnelor clinice sun formă de paroxism, alterarea sau nu a cunoştinţei, convulsii clonice–tonice, muşcătura limbii, incontinenţa de urinara (9). Starea bioelectrică cerebrală, ce include paroxisme de descărcări anormale sub formă de unde patologice corespunde tipului de criză catamenială. Nu au fost decsrise particularităţi electrice ale creierului pentru crizele catameniale.

Scopul

Descrierea caracterului corelativ dintre crizele epileptice catameniale şi paroxismele de anormalităţi electrice cerebrale la femei de vârstă reproductivă.

Materiale şi metode

Pentru studiu au fost selectate 10 paciente cu epilepsie, crize tonico-clonice primar sau secundar generalizate şi crize focale cu exacerbarea lor dublă în duferite pattren–uri ale ciclului menstrual. Frecveţa medie a crizelor într-un ciclul menstrual s-a echivalat cu 5. Vârsta pacientelor extinsa de la 12 la 40 ani, greutatea corporală 50-72 kg. Până la includerea în studiu s-a efectuat examinarea medicală generală şi ginecologică. Nici una dintre paciente nu a folosit contraceptive orale, nu a suportat intervenţie chirurgicală ginecologică, întrerupere de sarcină sau naştere în ultimele 6 luni. Electroencefalograma s-a înregistrat în laboratorul ştiinţific „Neurobiologie şi Genetică Medicală”, prin metoda video-EEG de rutină, la electroencefalograf computerizat „DELTAMED”. Evaluarea s–a efectuat în Clinica de Neurologie şi Neurochirurgie, CNŞPMU.

Diagnosticul de epilepsie catamenială s-a stabilit în baza calendarului de evidenţă a crizelor şi ciclului menstrual. Atribuirea ciclului menstrual către ovulator sau anovulator s-a confirmat prin aprecierea temperaturii bazale corporale (TBC). Cercetarea s-a efectuat pe parcurs de 3 luni. Au fost evaluate 30 de cicluri menstruale, s-au înregistrat 90 EEG (câte 3 la fiecare ciclul menstrual în C1, C2, C3).

Rezultate

Descrierea semnelor clinice ale crizelor catameniale au pus în evidenţă prezenţa dominantă a alterarii cunoştinţei (85%), care include stări de confuzie, dezorientare temporo-spaţială până la pierderea cunoştinţei. Cu aceeaşi predominanţă se descrie amnezia postictală. Automatismele mixte s–au apreciat în 40% cazuri în contextul crizelor focale complexe. Convulsiile clonice, muşcătura limbii şi incontinenţa de urină s-au descris în 2/3 cazuri, fiind prezente în toate tipurile de criză cu alterarea cunoştinţei.

La cele 10 paciente incluse în studiu au fost înregistrate 90 de electroencefalograme. Numai în 2 cazuri, cea ce a constituit 20% s-a vizualizat amplificarea după frecvenţă şi amplitudine a descărcărilor epileptice de tip „spike şi vârf-undă” în timpul probelor funcţionale. În restul examinărilor, traseul EEG a rămas constant – paroxisme similare de descărcări cu unde-vârf şi spike-uri s-au înscris în aceleaşi regiuni cerebrale în toate pattern- urile catameniale.

Desenând dispersia crizelor, s-a observat o prevalenţă de 70% a crizelor focale simple motorii în faza premenstruală a ciclului şi 60% a crizelor focale complexe cu generaliazre secundară, ciclurile fiind ovulatorii. În faza luteală a ciclului anovulator prevalenţa crizelor a constituit 80%. Crizele primar generalizate s-au manifestat în 1/5 cazuri.

Tabelul 1

Semnele neurologice ale crizelor epileptice catameniale

N	Fenomenologia clinică	%
1.	Alterarea cunoştinţei, inclusiv pierderea	85%
2.	Automatisme (verbale, motorii, ambulatoriu)	40%
3.	Convulsii tonice	60%
4.	Convulsii clonice	80%
5.	Crize tonico-clonice primare	20%
6.	Crize tonico-clonice secundare	40%
7.	Crize focale	20%
8.	Muşcătura limbii	60%
9.	Incontinenţă de urină	60%
10.	Aura mixtă (vegetativă, sensitiv-sensorială)	60%
11	Amnezie postictală	85%